Demand meter



Au 6, 1935. J. H. STARK DEJMAND METER Filed Sept. 27, 1934 Invenoorn Juliam H.Ebamk. /-f

Hia btovnne q Patented Aug. 6, 1935 UNITED STATES PATENT OFFICE DEMAND METER Julian H. Stark, Fort Wayne, Ind. assignor to General Electric Company, a corpora.tion of New York My invention relates to maximum demand meters and has for its object improvements In thls form of meter wh!ch reduce costs and increase the convenlence. reliability and accuracy of this form of meter. In particular, my Invention relates to an improvement in the timing lnterval mechanlsm which performs or controls the resettlng operatlon at the encl of a. demand perlod, whereby the demand period may be easlly changed and whereby the time consumed in a. resetting operation ls materially reduced.

The features 015 my lnvent1on whlch I believe to be novel and pa'oentable will be polnted out in the claims appended hereto. For a better understancllng of my Inventlon reference 15 made In the following description to the accompanying drawlng In whlch Fig. 1 represents a. perspective und somewhat expanded vlew of the operating parts cf my demand meter Includlng the circult connections thereto. and Fig. 2 is a. face vlew of the meter showlng the preferred arrangement 01 the djfferent lndicating scales a.nd polnters thereo1.

Referrlng to F1g. 1 of the drawlng, II represents some lntegratlng meter the demand 015 which is to be indicated over a suitable demand period. such as fliteen minutes er slxty mlnutes, Ior example. The demand meter o! my Inventlon Is represented as a. separate device anti is actuated through a system of electrlc Impulses. the frequency of whlch Is proportional to the ram of rotatlon o! meter II. A shaft I0 extends from meter II und operates a palr o1 cams I2 und I3 whlch are arranged In staggered relation so that thelr teeth alternate wlth ea.qh other. Thls system ot' cams and the contact members I4. I0 and I'I assoclated therewit-h are employed to send Impulses to the demand meter 01 my Inventlon, and In order that a. clear understanding o! I:his Impulse system may be had, II. will be deslrable to explaln this contact mechanlsm a.t

the Integratlng meter II.

The ca.ms I 2 and I3 are made of Insulgting ms.- terial und the contact members are made o1 reslllent conductlng materlal und are supported by the lnsulatlng block 0. The double contact mcmber I4 extends beneath both contact members I 6 a.nd I'I. The tree ends o! contact members I8 und I'I rest on cams I2 und I3 respectively with sllght tension so tha.t as the staggered cams rotate the contact members I0 und I'I are alternatcly ra.lsed and lowered. Member I0 ha.s Just dropped from the hlgh polnt o1 Its cam I2 und in so deine I: has contacted with member I 4 slIghtly lowerlng the la.tter brea.klng contact betwern lt and contact member I1. As the cams rota.te further In a clockwise dlrectlon mexnber I'I will drop and make contact with I0 and Interrupting the contact between I6 und I4. Contact 11mmber I4 ls connected I:o a wire 2 containing a source of supply I5 und contact memb'ers I6 and I1 are connected to wires I an 3 respectlvely. Wires I, 2, and 3 run to the operating solenoid of my demand meter. This solenoid has two coils I8 und I9 spaced apart and axlally arranged and reciprocate a plunger 22 to whlch there :Is cannected a lever 24 for operating the demand gear tra1n of my demand meter and a lever 23 comprising a, portion cf a toggle swltch having two Sets of conta.cts 20 und 2 I. Contacts 20 a.re counected in wlre I between the dlstant integratlng meter II and solenold co1l I8. The other set of contacts 2I Is connected in the wire 3 and the clrcult of coll I 9 of the solenold. The wlre 2. which contains the source oi supply. has a. common connection to the other terminals of coils I8 ancl I9.

The arrangement 1s such tha.t Impulses a.re transmltted. Irom the contact device cf meter II. first over a clrcult comprising wires I and 2. and then over a. circult comprlsing wires 2 and 3 In an alternate sequence and at a rate propor- Iional to the rotatlon 01 meter II. These 1mpulses a.re recelved on the coils I8 and I9 of the solenoid through the contact of the toggle switch 23 which breaks the circuit nver whlch an in;- pulse has just; been recelved and completes the other clrcuit so that on the receptlon cf the next alternate Impulse, the other coil of the solenoid will be energlzed und its plunger operated in the reverse directi on. AI: the meter II, the circuit ls shown a.s closed over wires I axicl 2, and the Impulse which has been transmitted over this circult has operated the plunger to the posltion shown and opened the clrcult at contacts 20, at the same time closing the circuit: 01 wlres 2 and 3 at coz'1tacts 2I. As meter II rota'tes, a. counectlon will shortly be made at thIs polnt between wlres 2 und I whlch will energize coll I 3 01 the sole'nold und reclprocate the plunger 22 to the opposlte position from that whlch ls shown, open- Ing the contacts at 2I and closlng them a.t 20.

Thls form of Impulse system has the advantage that It does not consume an unnecessary amount of electrlc e=nergy because just as soon as an 1mpulse ls sen und received, the recelvlng device interrupts the Impulse even should the meter II stop entirefiy. There is little tendency !or these contacts to chatter and, even 1f chatterlng does occur. II; will result lnno false operation of the 55 solenold at the receiving end. The toggle swltch operated by lever 23 provides a quiok make and break of the circuit at this point. It will be understood that the toggle switch ls so arranged that the circuit of a solenoid coi1 is not broken until the. plunger has substantially completed ll;s movernent and moved the toggle beyond the dead center after whlch the toggle itself will complete the movement. The toggle serves also to hold the plunger of the solenoid in the posi- Lion to which lt was last operated and tl1is solenoid clevlne will, therefore, operate reliably in any angular position, tha.t ls to say, the plunger might be vertical, lf so deslred. Due to these features as above descrlbed, the impulse system ls very reliable.

'I'he lever 24, which is also operated by (he plunger 22, operates 011 a ratchet wheel 25. These parts 24 and 25 may be termed an escapement ratchet slnce this mechanism combines the function of a pawl und ratchet; for rotating the wheel 25, anal the functlon of an escapement whlch posltively limits the amount: of advance of wheel 25 for each operation of the solenoid. lhe face of wheel 25 5.s provlded with eight triangularshaped teeth 28. 'I'he lever 24 is provided with an oflset a1*c-shapecl upper portion 29 which reciprocates from one periphery of wheel 25 to the other between the teeth thereon. The upper surface of portion 26 engages the slanting surface ot a teeth 28 as part 29 moves to the righc as viewed in Fig. lrotating wheel 25 one-sixteenth revolution in a counterclockwise directlon. The lower surface of part 29 engages the slantlng surface of a tooth as part 29 moves to the left 120 rotate the whee1 anocher one-sixteenth of a revolution in the same direction. 'Ihls arrangement positlvely drlves the wheel 25 icrward in steps at a rate determlnecl by the impulse rate and at the same Urne lt locks wheel 25 froxh rotatlon elther forward or backward between the receptlon of impulses. 'Ihis device ls, therefore. not subject to over-shooting as sometimes occurs with an ordlnary paw1 and ratchet devlce and lt has the additional advantage that no extra pa.wl ls neoessary to prevent backward rota.tion.

The shaft 26, which ls advanced in accordance with the impulse rate by wheel 25, may be providecl with a plnlon 30 whlch drives an impulse totallzing register indlcated at 3l where lt ls desirecl to totallze the Impulses. 'Ihls ls possible beoause the shaft; 26 1s drlven with ample torque. Shaff. 26 also drlves a plnlon 32 whlch ls spllned on shafr, 26 and always rotates therewlth but is movable along the shaft lnto and out of drivlng engagement w1th a gear wheel 33 cf the demand meter gear traln. The purpose of thls gear traln, whlch lncludes gear 33, pinlon 4l ancl geax 35. ls 120 advance the demand meter dog 34 and move a frlctlon polnter 42 up sc'ale. The dog 34 1s reset to zero, which ls the posltion shown in the drawlng, when gear 32 lsmoved out o! mesh with gear 33 at the end o! a. demand 1nt erval.

The parts whlch are reset to zero are in general slmllar to prevlous devlces o! thischaracter wlth the excepnlon that the present device 1s provlded wlth an arrangement to eliminate back-lash in the demand meter gear traln and to exactly fix the rotatlve posltlon o! the teeth In gear 33 so es to mesh with plnion 32 wlthout clashlng 01 the gears and without rotating the gea.rs in elther dlrectlon when such engagement takes place followlng a resetting operation. In thls mangement the dog 34 and gear yvheel 35 are fixed to the shaft 36. A spring 31 ls colled about the shaft 36 and is fastened at one end to gear 35 and at the other encl to an abutment, 38. Tluis spring is wound up when gear 33 1s advanced from a zero position during a demand interval and serves to return the parts to zero position agflain wnen pinlon 32 is disengaged from gear 33 at the end of such demand interval. The zero stop, shown als 39, is not directly connected with shaft 36 r the other parts secured thereto but rather this zero stop is mounted on a gear 40 which has a bearing on .shaft 36. Both gears 35 and 40 mesli with plnlon 4I which plnion is secured an the sam.e shafl: with gear 33. When the parts are in the zero positlon shown there exists an initial tension in spring 31. As a result ol' this arrangement. there is no back-lash between pinion 41 and gear 35 at any time. and consequently there is n0 error in the aclvance of dog 34 due to bacx-lash in the gear train. Furthermore, gear 33 is returned to exactly the same zero position each time so that it ls a simple matter to have the teeth in plnion 32 exactly align wlth the depressions between the teeth in gear 33 when pinion 32 is slld into driving engagement. It was polnted out above that whee1 25 is advancecl exactly one-slxteenth revolution per Impulse. If. then, pinion 32 has slxteen teeth. these teeth will always assume a certain definite rotary posltion when shaft 26 is stationary whlch ls most 015 the tlme since shaft 26 rotates in steps. The zero posltion of gear 33 is, consequently, made such as to have proper alignrnent of lts teeth wlth pinlon 32 wh en the latter is in sorne one of lts stationary positlons so that the gear; are meshed without clashlng and without the nwcessity of rotating either gear forward or backward to effect this engagement.

From the above lt will be seen that the possibility of error creeping into the lmpulse system, in the ratchet escapement, ln the demeshlng arrangement, und in the demand gear train, has been reduced to a. minlmum. At the same time the parts are relatively 1'ew in number and s'mple in construetion. The solenoid advancing mechanism gives hlgh torque und the spring 36 may therefore be of sufllcient tenslon as to quickly and posltlvely return the dog to zero. This mechanism therefore has ample torque and ma.y be 01 rugged construction and does not require delicate adjustment o! the ratio cf torque to frlction in order to safcguard against tallure.

The Iriction polnter 42 indicates the maximum demand on a suitable scale 43, whlch scale may be three hundred degrees er more in length, es shown, 1'or example in Flg. 2.

The tlming mechanlsxn employed to momentarlly demesh the demand gear traln et plnlon A 32 at the end o1 a demand interval is arrange l to permlt changlng the length of the demand interval over a. wlde range in a very simple manner and without altering the short perioc l o! time during whlch plnlon 32 is dlsengaged 111 a resettlng operatlon.

'Ihe .timing devlce I3 represented as a small self-starting synchronoug motor 44 having an enclosed speed-reducing gea.r chamber 45. It will be assumad tha.t the terminal sha1't 43 .has a spiaed ot one mvolution per mlx'xute. 011 shatt 43 is secured a. dlsc 41 in wh1ch one or more laterallyextendlng plus are inserted nea.r the perlphery. The disc ls provlded wlth four equally-spaced holes lnto whlch these p1ns may be secured as by a screw und tlm'ead arrangement. The number and arrangement 01 plm: to be used will clepend upon the demand interval desired as will subsequently be explained.

The pins in disc 41 engage with slots in a dlsc 49 to forrn a Geneva drive. There are five s1ots in the disc 49 so that with one pin in disc 41. disc 49 will be advanced in steps at the rate of one revolution in five minutes. If there are two diametricaliy opposite pins in the disc 4T, the Geneva disc 49 will be advan.ced in steps at; the rate of two revolutions in five minutes. The m0- t.on of disc 40 may beconsidered as divided u.p into a series of motion impulses, each of equal magnitude, but by changing the number of pins in disc 47 these motion impulses of disc 49 occur more or lass frequently. The quick advance of disc 49 during a motion impulse is always the same. A light spring 50 is provided bearing against the periphery of disc 49 to click into the slots in disc 49 in its fivc difi"erent stopping positions to aid in exactly positioning the slots to be engaged by the pin in disc 41 and to prevent rotary movement of disc 49 exc6pt as moved forward by the G8neva drive.

Disc 49 drives a pinion 5I and thls pinion meshes with a ca1n gear 52. The gear ratio between 5I and 52 is assumed to have a speed reduction of twelve to one, although the invention is not limited to any particular gear ratio here. The carn gear 52 has a pin 53 extending from its side near the periphery and the end of this pin is cam shaped so as to engage and rock a 1ever 54 as the carn pin 53 moves past the adjacent end 01 this lever. The upper end of the 1ever is forked and engages in a. slot in a. co1lar secured to pinion 32 so that, as the Iever 54 is rocked back and forth, pinion 32 is slid back and forth ori shaft 26 out of and into mesh wlth gear 33. A light spring represented at 55 biases the 1ever 54 towards cam gear 52 and rturns plnion 32 to the in-mesh position imrnedlately following a demeshing operation. It will be noted that there are two additional openings 56 in cam gear 52 spaced with respect to each other and to the cam pin 53 by one hundred and twenty degrees. These openings are provided for the insertion of addii0nal cam Pins similar to cam pin 53 for C61- tain demand intervals as will subsequently be explained.

It will now be seen that with one pin in disc 41 and one cam pin 53 in gear 52, the gear 32 will be demeshed once per hour. This is because shafb 46 rotates at one revolution per minute, the Geneva disc 49 is advanced in steps at the rate of one revolution in flve minutes, and gear 52is advanced in steps at the rate of one revolution per hour. A variety o! other demand intervals may be had by adding pins to disc 41 and cam pii'ls to gear 52 as shown 'oy the following table:

The engaging suri'aces o1 cam pin 53 and 1ever 54 are made such tha.t a complete demeshing and meshing operationpf plnlon 32 and gear 33 takes place withln one of the torward motion impulses 015 gear 52. In all cases given, this gear 52 is stepped forward one-sixtieth part of a revolution per motion Impulse, the engaging surfaces between cam pin 53 and lever 54 are dimensioned so as to completely perform their operations within one-sixtieth revolution of the cam pin and are so positioned that such resetting operation is completed within one of the forward motion im pulses of the cam pin 53. I have found that a complete resetting operation may be performed in a practical and reliable manner by this mechanism in Lwo seconds which is a sufiicient length of time for the demand dog 34 to be reset to zero from any position and weil Within the time consumed by a single forward motion of impulse 0f cam pin 53.

It will be evident that this resetting operation interval of two seconds is the Same regardless of the demand interval which is selected, that is to say whether the demand lnterva1 be five minutes or one hour, it requires only two seconds to complete a resetting operation. Because this resetting period remains unchanged when the demand intcrval is changed, a change in the demand interval does not in any way afiect the design and operating characteristics of -any part of the demand metex.

It will further be noted that, in the case of a five minute demand interval and a two second. rasetting interyal, the percentage of time of the complete demand interval during which the gear 32 is demeshed is about 0.7 per cent. In a one hour demand intterval lt is about .05 per cent.

The probable per cent error due to the possibility of the reception of an impulse during a resetting operation is, of course, less than the percentages given above.

It may be stated that in a usual torm of prior art demand meter, diflerent demand periods were obtained by changing the gear ratio in the timing-interval train and that the time required Lo perform a resetting operation was proportional to the demand interval. In such prior art demand meters, the nme consumed in a resetting operation expressed in per cent cf the demand period, was therefore constant and moreover generally greater than 0.7 per cent which is the maximum percentage resetting time in the meter of my invention a.s described above.

. I consider that the improvement that I have made in the timing-interval mechanism in this respect to be an important advance in the art. According to my invention, the gear ratio between the timing motor and. 'resetting cam is changed in the sense that the demand interval .mny be changed but the forward-mution impulses of the timing train always remain the same and, since a resetting operation is completed during one 015 these Impulses, the apparatus may be designed to reduce this resetting period to a minimum for all demand perlod.s 1'or which the meter may be used. The rotary motion of the synchronous motor drlven shaft 46 may be saicl to be broken up by the Geneva. movement into forwia.rd motion Impulses 01 equal magnitude and time duration. interval between these motion Impulses is greater than for a short demand perioc 1 but In elther case a resetting operation is completed during one of these equal motion Impulses.

' This Iorm 01 t iming-lnterval mechanism and the use of synchronous motors permit cf a number 01 demand meters to be exactly synchronized as regards their resetting tlmes. In Fig. 1, 51 may be taken to represent a synchronou.s motor For a long demand period. the

of a, second demand meter similar to the one represented in detail which has Its resettlng' time synchronized with the demand meter represented by having the synchronous motors of these dernand meters connected to the Same source cf alternating current supply and. their tIme-Inter- \-al mechanism similarly adjusted.

In many Instances lt; is desirable that a demand meter be arranged to give an indication of the amount of time remaining In a. demand Intenul und the meter of the present; invention may be easily arranged to provide such an Indication. For this purpose, I have provided the pointer 58 which is geared to shaft 48 of the synchronous motor so as t;o make one complete revolution during a. demand period and to indtcate at all tirnes the period remaining in a. demand interval on a. suitable scale 59. The gear ratio between pointer 58 and shaft; 46 should be changed when changing the demand interval where such an indicator 58 Is used.

The face view of such a demand m-cter may have the appearance of Fig. 2 where 3l represents the totalizing register, 42 the demand meter friction pointer and 43 its scale, aml the pointer 58 and dial 59 the parts for indicating the tlme remaining in a. demand Interval. It will, of course, be evident that one or both of the Indicating parts 31 for totalizing the Impulses and the pointer 58 for indicating the portion of demand period remaining may be omltted, II desired. It will also be apparent to those skilled in the art that the improvements In the timing interval x'nechanism hereinbefore described may be incorporated In dexnand meters generally und. employlng other forms of resetting devlces.

In accordance with the provisions of the patent statutes, I have described the principle cf operation 015 my Inventlon together with the apparatus which I now consider to be the best embodlment thereof, laut I deslre to have it understood that the apparatus shown Is only illustrative and that the Invention may be carried out by other means.

What I clsim as new and de=lre to secure by Letters Patent of the United States Is:

1. A demand meter comprlsing a. demand-mea&

uring part, means for advanclng sa.id part from a zero position In accordance with the demand to be mea.sured means for resetting sald part toa zero position, und tlrning Interval' means for determlning when sald part will thus be reset comprising a, timlng motor, a. Geneva. movement driven by said motor, a.nd means driven Irom sald Geneva movement for controlling sald resettlng operation such that euch such resettlngoperation Is completed within a single motion Impulse period 01 seid Geneva movement.

2. A demand meter comprising s. demand measuring part, means for advanclng sald pa.rt trom a-zero positlon In accordance w1th the demand to be measured. means for resettlng said part to a. zero position, und. timing Interval meanslor determinlng when such resetting operations will occur comprislng a. constant-speed timlng motor a. moement 1'or converting the constant rotary motion 01 said motor Into lntermlttent rotary Impulse movements o! equal m agnitude and du'- ration und having means for varying the numher (n) 01 such Impulse movements whlch shall occur during a. given period of t1me. und means driven from seid moveme'nt 1'or controlllng the resetting operatlon o1 said demand meter such tha.t a resetting operation will occur and be completed during euch nth motlon Impulse of said movement.

3. In a demand meter havlng a demand-measurlng part which Is advanced from a zero posit1on In accordance with the demand to be measured und which Is perlodlcally reset to the zero positlon at the end of each demand lnterval, a tlming Interval mechanism for controlling such resettlng operations and the timc thereof comprislng a constant-speed motor, a Geneva. movement driven Irom said motor for convertlng the constant rotary motlon of said motor Into quick Intermittent rotary movements, each 01 equal duration und magnitude, said Geneva. movement havlng mean's for varying the number (n) of the Intermlttcnt rotary niovements that shall occur during a given period of time, a rotary member driven by seid Geneva movement Tor. controlling the resettlng operatlon of seid demand meter such that a resettlng operatlon will be completed during one cf the intermittent rotary movements of said Geneva movement, said rotary member having adjustable muans whereby the number of resetting operations which occur during a complete revolution of seid rotary member may be varied.

4. A t1ming Interval mechanism for demand meters comprlslng. a constant-speed timing motor a disc driven theieby, a p1'n extending from the slde of said dlsc near Its periphery, a radially slotted disc mounted 1or rotation adjacent the first mentioned disc the slots therein being flve In number and uniformly spaced und adapted to be perlodically engaged by seid pln to produce Intermittent rotary movements o1 said slotted platze 01 revolution auch, a. wheel, a twelveto-one gear reduction drlve between said slotted platze and wheel whereby sald wheel is given sixty rotary Impulses to make.a complete revolution, and=reset control. means comprlslng a part rotated by said wheel and a relatively statlonary part posltioned to be momentarily engaged by the rotating part only during a. single rotary Impulse o! sald wheel and provisions for adding other plus to sald dlsc and other reset control parts to said wheel at diflerent selected polnts thereon to vary the number 01 such resetcontrol engagements made durlng a glven Interval of time.

5. A variable demand period timing Interval mechanism for maximum demand meters comprising, a rotary member having means thereon for controlllng a. resetting operation as sald rotary member rotates through a. small fractlon o1 a. revolution, a. consta.nt-speed timlng motor; speed-reduclng driving means connected between said tlming motor and rotary member said means also converting the constant rotary movement o! saId tlmlng motor Into Intermlttent rotary mdvements o! sai d rotary membereach o! equal dumtlon and magnItu-de, sufliclent to rotate sald rota.ry member through an angle to complete a. reset-controlllng operation, und means for vary- Ing the number o1 such Intermlttent rotary movements In a given period of tIme.

6. A t1me Interval mechanism for controlling the resetting operation ot niemand meters und the tlming Interval thereof comprising a. coustant-speecl timing motor having a terminal sha.it operatinget one revolucicn per minute, a. rotary reset control member, speed-reducing drlving means between sal'd motor und rota.ry member Includlng a Geneva. move ment such that saId ro ta.ry reset c'ontrol member 13 adva.nced by Inter- Inittent rotary movements, eanh e.qual to of a. complete revolutlon thereof and each movement being completed in 1ess than fifteen seconcls, und means for adjusting the Geneva. movelnent to vary the rate of such lntermittent movements to obtain 60. 120, 180, or 240 such movements per hour.

T. A tlme interval mechanlsm for controlllng the resetting opcration of demand meters anal the liming intervzal thereof comprismg, a constantspeed timing lnotor having a termlnal speed cf one revolution per minute, a rotary reset control member arranged to produce at least one resetcontrolling operation for each revolutlon thereof, driving means between said Lindng motor and said rotary controlling member including a. Geneva movement and a twelve-to-one gear reduc- Lion whereby the constant-speed movement; of sacl timing motor is converted lnto an intermittcnt rotary movement cf salcl rotary reset comt101 member requiring sixty such movements to complcte a rotation thereof, means for acljusting the Geneva movement to vary the rate of such interrn'ittent rnovements and means for varying the number of reset control operations performed by sald rotary member for revolutidn, whereby demand lntervals cf 5, 10, 15, 20, 30 and 60 minutes may be LLalned without alterlng the magnitude or duration cf the intermittent movements cf said rotary reset control member 8. A timing interval mechanlsm for demand mcters for controlling the resetting operations and the dernand interval of such meters, comprising a constant speed timing motor, a. rotary reset-controlling member, and means between said motor and rotary controlllng member for drlving the latter lncludlng a mechanlcal devlce for converting the constant rotary movement of sa1'd tlming motor lnto lntermittent; rotary movements at said rotary control member, and means for adjusting said mechanlcal devlce to vary the rate of such interrnittent rotary movements without varying their duration x magnitude.

9. A demand meter comprising, a driving gear' which 1s rotated in accordance with the demand to be measured, a demand-measuring member, a driving connectlon including a gear train between said drlving gear and m easuring member an inltially-tensioned spring connected to the mensurlng member end. of said gear train so as to be further tensioned when said gear traln is advanced by rotation of sald driving gear, tlme coutrolled means for momentarily demeshlng sald drive gear from said. gear train to allow said spring to return the gear train to a zero posltion at the end of, demand-measuring lntervals, means for stopping' such return movement at the zero posltion comprlsing a stop gear whlch ls blocked agalnsl: backward rotation in the zero posltion thereof, whlch ls not included in sald drlvlng connectlon but whlch 1s meshed with the drlving end of the gear traln, said arrapgement servlng to eliminate all back lash in the driving gear traln which ls returned to a zero posltlon and to posltion the demeshed gear thereof in a definite rotary position upon 1ts return to a zero posltion.

10. A dema.nd meter lmluding a. drlvlng gea.r which ls intermlttently advanced in equal steps in response to a measurement, 21 demand-measurlng parb lncludlng a gear driven by sald drivlng gear, means for momentarily demeshing sald gears to allow the return of the demand-measuring part to a zcro posltion, means for returnlng said pa.rt 'to a zero positlon when said gears a1e demeshed, sald drivlng gear having a. number of teeth equal to or a. multiple of the number of steps required to rotate sald gear a complete revolutlon such that, when stationary, lts teeth always assume a. similar oriented position, and means for posltioning said driven gear wlth lts teeth in proper meshing alignment wlth the drivlng gear when the latter is in any one of lts statlonary positlons upon the return of said dema.nd-measurlng part t0 a zero position.

11. A de mand meter inclucllng a. drivlng gear which is advanced in equal steps in response to a. measurernent, a demand-measuring gear train having at; une end a gear driven by said driving gear, means for momentarily demeshing sald driving and driven gears ab the end of demandmeasuring lntervals, an initially-tensioned spring connected to the other end cf the demand-measurlng gear traln whwh 1s further tensioned when sald traln is advanced for returnlng the traln to a zero position when saicl gears are demeshed, and means for stopping the driven gear in a definite zero posltlon upon such return movement wlth all of the back lash in said gear train taken up due to the initial tenslon of said spring, said drlving gear having a number of teeth equal to Q1 a multiple of the number cf advancing steps mereof requlrecl to make a complete revolutlon so that, when in a statlonary posltion between advanclng steps, its teeth a.lways assume a. slmilar orlented posltion, sald positlon being such that the drivlng and driven gears may be meshed without rotation of elther when the latter ls in its zero posltlon.

12. A demand meter of the type which ls advanced in response to electric Impulses. comprising a rotary member having a plurality of evenly-spaced lnwardly projecting teeth arranged in a. circle about; the axis of rotation of said member. a lever pivoted to reciprocate between the teeth on opposite sldes of the circle lnto aml out 013 engaging relatlon therewith, the? engagil.g surfaces of said teeth and lever belng such that sa1d member 1s advanced in one directlon in equal steps as said lever is reciprocated and is locked agalinst rotation by said lever when stationary, an electromagnet. responsive to electric-measurlng impulses for reclprocating sald lever, a demand-measuring part advanced by sa.id rotary member havlng drlving and drlven gears arranged to be momentarily demeshed in the operatlon of sald meter, sald drlving gear havlng a number of teeth such that lt 1s advanced exactly the cllstance o1 one or more teeth for each step-by-step rotation of sald rotary member whereby lts teeth always assume a. slmllar oriented posltlon in all 01 1ts stationary positions.

JULIAN H. STARK.

DISOL.AIMER 2,010,705.Julian H. Stark, Fort Wayne, Incl. DEMAND METER. Patent d&ted August 6, 1935. Disclaizner filed September 28, 1935, by the assignee, General Etactric Company.

Hereby enters tl1e following disolaimer of claims 9, 10, and 11 0f the said Letters Patent, wl1ich are in the following W0MS, to wit:

9. A demand neter con1prising, a driving gear which isrotated in accorclance with the demand t0 be lneasured, a demand-measuring member, a driving connection including a gca.r t1*ain between said driving gear and measuring member, an initiallytensioned spring connected to tl1e mea=uring member end of said gear train so as to be further tensioned when said geur train is advanced by rotation of said driv1'ng gear, time controlled means for momentarily demeshing said drive gear from said gear train to al.low said spring to return the gear trai1'1 to a zero position at the end of de mand-measuring intervals, means for stopping such return movement at the zero position comprising a stop gear which is blocl.*ed against backward rotation in the zero position thereof, which is not included in said driving connection but which is meshed with the driving end of tl1e gear train, said arrangement serving to eliminate all back 'lash in the dn'ving gen! train which is returned t0 s, zero position and to position the derheshed gear thereof in a definite rotary position upon its return to a zero position.

10. A demand meter including a driving gear which is intermittently advanced in equal steps in response to a measurement, a demund-measvring part including a gear driven by said driving gear. means for moment-arily demeshing said gears to allow the return 0f the demand-moasuring part 130 a zero position, means for returning said part t0 a zero position when said gears are demeshed, said driving gear having a. number of tecth equal t0 or a multiple of the number of steps required to rotate sa.id gea.r 21 complete revolution such that, when stationary, its teeth always assume a similar oriented position, and means for positioning said driven gea.r with its teeth in prnper meshing alignment with the driving gear when the latter is in any one of its stationury positions upon the return of said denmnd-measuring art to a zero positi'on.

11. A domand meter including a driving gear. which is a vanced in equal steps in response to a measurement, a demand-rneasuring gear train having at one end a gear driven by said driving gear, means for momentarily demeshing seid driving a.nd dnven gears at the end of demand-measuring intervais, an initially-tensioned spring couneoted t0 the other end of the demand-measuring gear tra.in which is further tensioned when said train is advanced for returning the train to a zero position when sz a.id gears are demeshed, and mean.s for stopping the driven gear in a, definite zero pos1tmn upon auch return movement with all of the back lash in said gea.r tra.in taken up due to tbe initial tension of said spring, said driving gear having a number of teeth equal to 01 a multiple of the number of advancing steps thereof required to make a c omplete revolution so tbat, when in a stationary osition between advancing steps, 1ts te ath always assume a similar oriented position, sa.id position being such that the and driven gears may be meshed without rotation of either when -the latter 1s m 1ts zero position.

[Qfiioial Gazette October 2.9, 1986.]

DlSOLAIMEF2 2,010705.Julian H. 'S'taflc, Fort Wayne, Ind. DEMAND METER. Patent dated August 6, 1935. Disclaimer file d September 28, 1935, by the assignee,

General Electric O0mpany, Herebyenters the following disclaimef of claims 9, 10, and 11 of the said Letters Patent, which are in the following words, to wit:

9. A demaind meter comprising, a driving gear which is rotated in accordance with the demand to be measured, a demand-measuring Inember, a driving Connection -including a gear tiain-between said driving gear and measuring member, an initiallytensionedspxing co1tmet ted tq the measuring member end of said gear train so as to be further tensioned when seid gear train is advanced by rotation of seid driving gear,

time Controlled means for momentarily demeshing said drive gea-r from said gear train to allow said spring to returnthe gear trai1i to a zero position at the end of demand-measuring intervals, nieans for stopping such return movement at the zero position comprising a stop gear which is blocked against backward rotation in the zero position thereo f, which is not ineluded in said driving connection but which is meshed with the driving end ef the g'ear train, said arrangement serving to eli1m'nate all back 'la sh in the driving gear train which isreturned to a zero position and to positio nthe den'1eshed gear thereof in s definite*rotary position upon its return to a zero pos1t1on.

10. A demand meter incl'uding a driving gear which is intermittentlyadvapced in equal steps in response to a mea,surement, a demand-measuping part mcludmg a gear driven by said driving gear means for mbmentarily demeshing said gears to all ow the return of the demand-measuring part to a zero osition, means for returmng said Pait to a zero position when s'aid gears are demeshed, said gear havinge number of teeth equal to or a multiple of the number of steps requ1red to rotate sa1 d gear a complete revolutidn such that, when stationa1y, its. teeth always assume a sum- 1er oriented position, and means for positiom'ng said driven gea.r with its teeth in proper meslung align ment with the driving gear when the latter is in any one pf its stat1onary positions upon the return of said demand-measuring art to aero pos1t1bn. 11. A demand meter including a driving gear Which is a van'ced m equal steps in response to a meas1irement, a demand-measuring ge'ar train having at one end a gear driven by sa.id gear, m6ans for momentarily demeshing seid driving an d dnven gears a1: the end of demand-measuring intervals, an initially-teusioned sprmg connected to the other end of the demand-measuring gear train which 1s further tens1oned when said train is a;dvanced for returning the train to a, zero position when said gears are demeshed, and means for stopping the driven gear in a, definite zero positionupon such return-movement with all of the back lash in said gear train takten up due to the im'tial tension of said spring, ssiidd1iving gear having a number of teeth equal to or a multiple of the number of advancing steps thei6of required to make a complete revolution so that, when in astationary position between advancing steps, its teeth a.lw ays assume a similar oriented position, sa.id p osition being such that the driving and driven gears r'na.y be meshedwithout rotation of either when the latter is in it zero positi0n.

Gazette Octebr 29, 1936;] 

